remove 32767px margin/padding values in main CSS

Several element id's were set to use "padding-bottom: 32767px;" and
"margin-bottom: -32767px;". This caused element targets (such as
http://sfconservancy.org/about/staff/#denver ) to be rendered poorly
in most browsers, by preventing the user from scrolling up. Removing
these lines appears to fix the rendering issue with no side effects
(in limited testing of the Staff page).

This change effectively reverts parts of 450ea2c and ed954b7 as the
32767px values were added in those commits.